The proposed study extends the PI's preliminary work and examines hypotheses on the developmental impact of complex partial seizure disorder (CPSD) on children's thought processes. It will identify the complex relationships between impaired thought processes (i.e., formal thought disorder and discourse deficits) and biological, cognitive, linguistic, and behavioral variables in pediatric CPSD. This research will examine if impaired thought processes in children with CPSD are associated with focal fronto-temporal involvement by comparing measures of formal thought disorder and discourse in these children to those of children with primary generalized epilepsy with absences (PGE) and to normal children. Within each seizure disorder group, this study will assess the developmental impact of early age of onset, frequent seizures, and elevated blood levels of multiple antiepileptic drugs on the severity of impaired thought processes. Due to the complex effects of the biological properties of epilepsy on the child's functioning, this study will also examine if the impaired thought processes of children with CPSD reflect attention/cognitive, language, and behavioral dysfunction. Finally, it will also determine if frontal lobe dysfunction is associated with the impaired thought processes of children with CPSD. If the study's hypotheses are confirmed, the findings of the proposed research will make three important contributions. First, they will identify impaired thought processes as a developmental disability that reflects the impact of the biological properties of CPSD on the maturation of children's thinking. Second, they will pave the way for educational detection and remedial intervention by replicating the PI's preliminary finding that CPSD subjects with IQ scores below and above average have respectively. Third, they will determine if children with CPSD have interictal language dysfunction and its relationship to impaired thought processes and cognitive dysfunction.